A correlation for overall mass transfer coefficients in rotating disc contactors

Both Henry's constants and volumetric mass transfer coefficients (KLa) of eight priority chlorinated organic compounds including 1,1-dichloroethene, methylene chloride, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,4-dichlorobenzene in an air stripping packed column were investigated in this study. The liquid and gas phase EPICS (Equilibrium Partition in Closed System) and direct calculating methods were applied to determine the Henry's constants of VOCs. The interference of co-solute on Henry's constants was also investigated. Experimental results indicated that decrease in Henry's constants of VOCs was observed in the presence of humic acid but no apparent effect on Henry's constants was detected when there was NaCl and surfactant in solution. Four different configurations of packing media including Intalox Saddle, Super Intalox Saddle, Telleret, and Hedgehog made of polypropylene were respectively packed in the air stripping tower and investigated in the study. The dependence of hydraulic loading, air-water ratio, and configurations of packing media on mass transfer coefficients of VOCs was discussed.

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Transport of chlorinated hydrocarbons between sewage and sewer atmosphere

Water Science & Technology ◽

10.2166/wst.1996.0476 ◽

1996 ◽

Vol 34 (3-4) ◽

pp. 557-564 ◽

Cited By ~ 2

Author(s):

Bettina S. Haas ◽

Reimer Herrmann

Keyword(s):

Mass Transfer ◽

Aromatic Compounds ◽

Chlorinated Hydrocarbons ◽

Transfer Coefficients ◽

Mass Transfer Coefficients ◽

Sewerage System ◽

Mass Fluxes ◽

Single Compound

Sewage containing volatile contaminants is a potential VOC-source in cities. Thus we tried to evaluate volatilization out of the sewerage system by measurements of contaminants in sewer gas and sewage. Our results from a medium sized town with little industry showed that sewer gas is mainly contaminated with alkanes, small aromatic compounds and chlorinated hydrocarbons. For three chlorinated hydrocarbons (chloroform, trichloroethene, tetrachloroethene) we determined mass transfer coefficients out of sewage and used these data to estimate mass fluxes from sewage and emissions out of the sewerage system for two sewer stretches. Considerable emission of chlorinated hydrocarbons from sewage, i.e. fluxes of some 10 to 100 g per m2·d, occurred only when the contaminant input via sewage was between some g and mg per litre for a single compound. For concentrations that were about 3 orders of magnitude less, emissions were negligible.

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The calculation of mass transfer coefficients and of axial dispersion coefficients from concentration profiles

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19653822 ◽

1965 ◽

Vol 30 (11) ◽

pp. 3822-3833 ◽

Cited By ~ 9

Author(s):

V. Rod

Keyword(s):

Mass Transfer ◽

Axial Dispersion ◽

Concentration Profiles ◽

Transfer Coefficients ◽

Dispersion Coefficients ◽

Mass Transfer Coefficients

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Mass Transfer in Liquid in an Apparatus with Mobile Packing. Application of a Dispersion Model

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19931078 ◽

1993 ◽

Vol 58 (5) ◽

pp. 1078-1086

Author(s):

Zdeněk Palatý

Keyword(s):

Experimental Data ◽

Mass Transfer ◽

Empirical Equation ◽

Dispersion Model ◽

Transfer Coefficients ◽

Mass Transfer Coefficients

The paper deals with the mass transfer in a liquid on a plate with mobile packing. A procedure has been suggested which enables estimation of the mass transfer coefficients from experimental data considering the dispersion flow of the liquid. The results obtained from the desorption of CO2 from water are presented graphically and in the form of empirical equation.

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On the convective diffusion under partial slip at wall

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19890967 ◽

1989 ◽

Vol 54 (4) ◽

pp. 967-980 ◽

Cited By ~ 3

Author(s):

Ondřej Wein ◽

Petr Kučera

Keyword(s):

Mass Transfer ◽

Numerical Solution ◽

Analytic Solution ◽

Convective Diffusion ◽

Linear Velocity ◽

Partial Slip ◽

Accurate Calculation ◽

Transfer Coefficients ◽

Empirical Formulas ◽

Mass Transfer Coefficients

Extended Leveque problem is studied for linear velocity profiles, vx(z) = u + qz. The existing analytic solution is reconsidered and shown to be inapplicable for the accurate calculation of mean mass-transfer coefficients. A numerical solution is reported and its accuracy is checked in detail. Simple but fairly accurate empirical formulas are suggested for the calculating of local and mean mass-transfer coefficients.

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